RUN247 / Features / Realtime Metabolic Testing with Lumen

Realtime Metabolic Testing with Lumen

We have no shortage of gadgets to help us through the day, reminding you that you went upstairs 27 times, tracking our training, checking our heart rate, confirming its raining and that’s why you are drenched!

What about a gadget to help us lose weight? A new electronic device called Lumen  has arrived via the Indiegogo funding platform and is out in the wild. We have a test unit and we have been trying it out but first, here’s a bit of background into how it works and what’s involved.


What is Lumen?

Lumen is a portable device to accurately measure metabolism. Lumen uses a CO2 sensor and flow meter to determine the CO2 concentration in a single breath. This indicates the type of fuel your body is using to produce energy. Daily use of the little device and the partnering app allows you to monitor, plan and control how your body is fuelled and what the body is using for fuel to accurately maintain a desired body weight or used to safely control weightless by ensuring the body is burning fat stored in your body.

Putting on weight

Putting on weight by the build up of excess fat is a pretty simple process. We gain weight when excess carbohydrates, proteins, alcohol or sugar in the body are converted into triglycerides and stored in fat cells throughout the body. The more we consume above our own bodies daily calorie requirements without reasonable activity to burn off the extra calories will get stored in the body.

As a guide, men need around 2,500kcal (10,500kJ) a day to maintain a healthy body weight, and women need around 2,000kcal a day (8,400kJ). Embarking on a strenuous training plan will mean you need to increase your calorie intake to fuel this extra activity.

Metabolism and your weight

Metabolism is the process by which your body converts the food you consume into energy for immediate use or to be stored for later. If you store more than you burn then typically you gain weight.

What are Metabolic fuels?

Your body relies on three main sources of energy:

  • Carbohydrates – Quickest and easiest to produce energy from.
  • Fats – Harder to produce energy from, but provides long, sustainable energy.
  • Proteins – Not a major source of energy as the body uses them primarily as building blocks.

Our carbohydrate storage is the chief regulator of energy in the body.

Fat is one of six nutrients your body needs, carbohydrates, proteins, minerals, vitamins and water. Of these six nutrients, carbohydrates, protein and fats provide calories. We need fats but too much fat being stored will lead to weight gain.

  • One gram of carbohydrate and protein yield 4 calories/gram.
  • One gram of fat yields 9 calories/gram.

As you can see, fat has twice the calorie count of carbs and proteins. To lose weight, you need a calorie deficit. One way you can achieve this is by eating less, consuming fewer calories and exercising.

What happens to fat?

When you lose weight, where does the fat actually go? Traditionally it was believed that fat was burned and converted to energy and heat or even converted into muscle mass. Recent research indicates that your lungs are the primary organ involved with fat loss and getting it out of the body in a process that converts the fat into a form that can be easily exhaled.

Essentially, you breath out converted fat with CO2 with each breath. It should be noted that resting respiration is not going to get you lean by itself! You will need to exercise and raise your metabolism to get your body into a state where it will convert the trapped fat to be exhaled by your lungs! The water formed may also be excreted in the urine, faeces, sweat, breath, tears etc. There a many articles available from trusted sources that go deeper into the science if you need further reading.

How can Lumen work with you to help you lose weight by measuring metabolism ?

There are two main ways to measure your metabolism:

RQ – Respiratory Exchange Ratio. Normally in a hospital/clinic with a costly and time-consuming test known as Respiratory Quotient which is a measurement through the blood
RER – Respiratory Quotient. Measured through analysing the breath

Lumen uses RER as the core data point to bring the same measurement to a home environment by measuring the CO2 in your breath through the sensor and flow meter, based on your RER metric. The CO2 concentration is measured using breath analysis, which is performed by inhaling a fixed volume of air through the Lumen device (dynamic to each individual), holding it for 10 seconds, and exhaling fully. You repeat this process at various points in the day so the device can get an accurate understanding of your body situation.

Metabolic flexibility means being flexible and able to alternate between using fats and using carbs as a source of fuel. This leads to sustainable weight loss, optimised workout performance, or weight maintenance. Healthy individuals can switch between their fuel sources, but better metabolic flexibility allows your body to do so more efficiently and quickly.

You have the ability to improve your metabolism through what you eat and your lifestyle habits. Each morning, Lumen determines the source of your body’s fuel — carbs or fats. Lumen provides personalised nutrition recommendations and daily guidance on sleep, diet, exercise and more.

In multiple studies, Lumen’s patent-pending technology was deemed to accurately measure metabolic fuel usage through analysing your breath when compared to the gold standard RQ (blood) for measuring metabolism. This testing is done in realtime at various parts of the day.

  • Low-carb diet, the body tends to use mainly fat storages as its primary fuel source, which is represented by a low RER.
  • High-carb meal, the body tends to use less fats for fuel, which is represented by a higher RER. Additionally, following a high-carb meal, the body tends to use available carbs in the digestive system, represented by a higher RER.

When using the Lumen device to assess changes in metabolic fuel usage, Lumen can reproduce the same trends described in widely accepted literature. The Lumen technology was found to effectively differentiate between different metabolic states of its user.

In a nutshell the Lumen device can accurately analyse the characteristics of you exhaled breath, suggest a daily diet and activity plan to help you fine tune your ability to lose weight through a measurable scientific process.

As an update we have been using the unit now for some time and the results have been positive. During our time together the Lumen team have introduced a link up with Garmin. The app now reminds you to use your device and you can check on the data.

“Lumen and Garmin devices sync your fitness data, sleep patterns, nutrition and more for a fully personalized experience. Get the most out of your Lumen with daily and weekly lifestyle insights and metabolic flexibility reports.”

The addition of the Garmin App is very useful and provides prompts to take a breath and displays your progress.

During our use the Lumen has been a reliable device, it’s solid build and premium feel make using the device a pleasure. Syncing to the mobile App has been without issue and since it’s launch has worked perfectly.

The device requires an inhalation and exhalation to analyse the molecular content of your breath to determine wheteher you’re burning predominantly carbs or fats. By regularly using the Lumen it will then suggest a plan for the day to help you achieve your desired results. This includes amounts and types of foods to consume.

The App becomes a very handy companion and the device is small enough to take with you in a packet or bag so you can use it throughout the day. Battery charge is ample for days of use without worry or need for a charger to be carried around. Depending on use, this will easily be days of solid use.

We found the device and it’s data to be very easy to use and interpret, the App being minimal and logical to navigate. The addition of the Garmin connectivity adds an extra level of useful support. The alerts being particularly helpful. The more you use the device the better the data a results will be.

As an extra device to help you fine tune your training for fitness or to help maximise weightless the Lumen is a great tool to help you understand what your body is doing and how to fuel it to meet your goals.

The simple to understand interface and instructions make it a doddle to use. There are plenty of helpful videos and tutorials to help you and make it foolproof. If you’re not creating through the device correctly it helps you and informs you. This means it should deliver accurate data to you with each use and correct usage of the Lumen will deliver trustworthy data.

In conclusion the Lumen seems to deliver on it’s promises and if you follow the advice offered from the App it should guide you to your target, be that weight or fitness. The information seems accurate and sensible.

If technology is your thing then this little gadget is very clever. If you’re a technophobe, it’s simple to set up and use.

lumen + Garmin

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